Yamamoto falls into the hole and meets face to face with one of the escaped convicts, Ken Joshima. Ken charges at Yamamoto but Yamamoto dodges and Ken puts something in his mouth. He then ricochets from wall to wall and attempts to bite Yamamoto who defends himself with his sword, which breaks due to the strength of Ken's attack. Ken then reveals that he is able to change his abilities to those of many animals by putting their fangs into his mouth. As a demonstration, he activates his Kong channel and uses his increased strength to throw Yamamoto. Yamamoto recovers and checks if he's injured. Just then, Ken uses his Wolf channel to sniff out the blood of the dog that he sprayed at Yamamoto and attacks but Yamamoto is able to dodge. As Ken attacks, Yamamoto continues to defend his body, causing Reborn to comment that Yamamoto is being especially careful to avoid injury due to his love of baseball.
Tsuna blames himself for bringing Yamamoto along and Reborn suddenly kicks him into the hole. Ken instantly switches targets but is stopped by Yamamoto who threw a rock at the back of his head. Ken swaps to Cheetah channel and charges at Yamamoto, dodging his second rock and biting his arm. However, Yamamoto used this opportunity to strike Ken in the head using his sword handle leaving Ken seemingly defeated. Tsuna immediately begins to apologize to Yamamoto for his arm but Yamamoto tells him that an arm is a fine sacrifice to protect a friend. The two then climb out of the hole and Reborn shows them a picture of their opponents.
Note: Bold + Italicized = First Appearance